The 
std.error s% 
and for pure field plots (volume determination) 
i 
ro 
ro 
OV 
( 
CD 
Cfq 
O 
H! 
n 
O 
s 
X 
I 
p 
a 
Cfi 
f—•• 
< 
o 
w 
< I 
CO 
l-h 
CD